Simple control valves

ABSTRACT

Simple fluid power control valves for use with pneumatic and/or hydraulic pressurized working fluids, of springless valve construction whose central longitudinal bore slidably receives a pin which is permanently secured with appropriate seals to allow it to float axially inside the bore, from a one closed position when the pin end with seal is subjected to the fluid pressure of the working fluid at the infeed valve end, to another open position when the opposing pin end is subjected to an external force which is greater than the fluid pressure end thrust at the infeed pin end, said external force being caused by pin actuation manually, by toggle, hand or foot lever, by a timer cam or by pilot pressure, said pin floating with seals, allowing for fast valve response as a result of short travel designed therein.

United States Patent Pauliukonis 1451 Dec. 19, 1972 54] SIMPLE CONTROL VALVES Richard S. Pauliukonis, 6660 Greenbriar Dr., Cleveland, Parma Heights, Ohio 44130 221 Filed: May 21,1971

21 Appl.N0.: 145,751

[72] lnventor:

[52] US. Cl .,l37/625.66, l37/625.27 [51] Int. Cl ..F16k 11/02 [58] Field of Search .....251/324; 137/625.27, 625.66

[56] References Cited UNITED STATES PATENTS 5/1968 Harpman l37/625.64

Primary Examiner-Henry T. Klinksiek [57] I ABSTRACT Simple fluid power control valves for use with pneumatic and/or hydraulic pressurized working fluids, of

springless valve construction whose central longitudinal bore slidably receives a pin which is permanently secured with appropriate seals to allow it to float axially inside the bore, from a one closed position when the pin end with seal is subjected to the fluid pressure of the working fluid at the infeed valve end, to another open position when the opposing pin end is subjected to an external force which is greater than the fluid pressure end thrust at the infeed pin end, said external 1 force being caused by pin actuation manually, by toggle, hand or foot lever, by a timer cam or by pilot pressure, said pin floating with seals, allowing for fast valve response as a result of short travel designed therein.

11 Claims, 6 Drawing Figures SIMPLE CONTROL VALVES 'The present invention provides control valves for transmitting pressurized fluid from a fluid supply to a receiver means for process control, or for directional fluid flow in which a receiver comprises an actuating power cylinder or a reciprocator, converting the pressure energy of the working fluid into linear motion.

Devices of this type which require fewer components for valve construction and operation are obviously desirable because they provide a simple, inexpensive and reliable means of controlling machines and operations in process or automation fields.

The valves simplicity in this invention lies in its construction: except for the elastomer seals,'only two components are involved, the valve body and the pin, regardless of actuator type, be it two-way valve for process ,control, or three-way or four-way directional valves used with power cylinders for fluid directional control, irrespective of actuation chosen, be it manual or pilot operated.

In one application these valves may handle hydraulic fluids or other media in liquid form, while the pilot operation is pneumatic, constituting applicational universality offered with simplicity combined to result in a considerable cost reduction and savings to the user.

These and other objects and advantages of the invention will become more fully apparent from the following description of the embodiment of the invention, taken together with the accompanying drawings:-

In the drawings:

FlGS. l-a and H; illustrate a cross-sectional view of the pin operated three-way directional valve embodyingthe invention, and a position change of the pin.

FIG. 2, showing a cross-sectional view of the control valve representing a design variation in which the pin actuation is performed by a pilot, includes an extra exhaust port and comprises three-way directional valve.

FIG. 3 shows a cross-sectional view of a two-way pilot operated control valve which is identical to the three-way valve except that the exhaust port is omitted here, illustrating another design variation with manifestation of simplicity in valve designs.

FIG. 4 illustrates a cross-sectional view of a pin operated four-way directional valve representing a manually actuated control valve design.

FIG. 5, showing a cross-sectional view of a simple control valve representing a design variation of a fourway pin operated valve in which pin actuation is performed by a pilot, includes an extra exhaust port.

Fundamentally all above valves incorporate two basic components, the valve body and the pin, plus elastomer seals as required, and are very similar, operating by a position change of the pin within the valve body proper, as controlled by either working fluid ing end provides the fluid infeed means, and terminates with a shoulder 2-a which may be countersink leading to a continuous smaller diameter bore 3 for the accommodation of pin 4 of differential diameter of which smaller diameter end 8 is slidably received therein and larger diameter end 7 protrudes outside the opposing housing end 5, said bore 3 terminating with an appropriate'countersink 6 at the other end as well.

Pin 4 comprises step 9 along its length where the two pin diameters of different sizes meet. Pin body 8 opposite a protruding end 7 terminates with an appropriate seal groove 10 provided with an elastomer seal 11 having an outside diameter 12 larger than the size of bore 3 to act as a stop against shoulder 2-a during the position change of the pin 4. Another elastomer seal 13 having outside diameter larger than the size of the bore 3 may be placed over pin body 8 and pushed against the pin step 9 securely to act as a stop during the opposite directional position change of the pin 4. Bore 2 can be provided with threads (not shown) or thread may be provided outside the housing as shown by 14 to connect to a fluid supply line. Fluid receiver port 16, also threaded, enters the valve inside bore 3 perpendicularly and exhausts via longitudinal annulus 15 leading toward the housing end 5 through which protruding pin end 7 carrying seal 13 extends. FlG. l-a

' identifies seal 13 away from countersunk housing end 5 with open exhaust found when working fluid energizes the fluid infeed port 2 by a fluid pressure which exerts end thrust upon the seal 11 of the pin body 8 large enough to keep the sea] 11 tight against the countersink 2-a preventing any further fluid flow and constituting a normally closed valve condition.

FIG. l-b identifies the position change in which the seal 11 is cracked open permitting fluid flow from the infeed port 2 via annulus 17 into receiver port 16 while the seal 13 closes the exhaust, such position change followed by an application of external force over the protruding pin end 7 by external means, be it manual push, tripper action synchronized with a machine such as a punch press running at certain constant stroking speed or a cam of anelectric motor-timer directly connected to said pin end 7- and exerting force large enough to overcome the end thrust the working fluid exerts over the opposite pin end. Upon the removal of such external force over the pin end 7, the working action upon pin area exposed to it, or by an opposing external force, be it a manual, tripper or pilot actuated force that overcomes the opposing end thrust of the working fluid pressure, and results in a position shift of the pin accomplished practically effortlessly primarily because of the small pin areas and respective small internal forces.

Shown in FIGS. l-a and l-b of the three-way valve design is valve housing 1 having a continuous central bore of slightly different diameters along the housing length in which bore 2 of larger diameter at one houspressure end thrust over the opposite pin end provided with seal 11 will shift pin 4 to original shut position defined as normally closed valve condition, shown in the FIG. 1 a, until the cycle repeats shifting the pin fromsaid normally closed position to another-exhaust position for as long as the external force is applied to the protruding pin end 7 while the infeed port 2 is energized with the working fluid, exerting a certain relatively small pressure, for continuous valve operation.

Because there are large clearances between the pin l060ll 0470 rather small overall dimensions of such valves, and thus reducing the overall cost. Finally, because of analogy in sealing'fluid supply and exhaust with simple elastomer seals rather than expensive poppets while principally approaching poppet action in the valve design of present invention, the valve travel is reduced to practically little and the valve closing speed is improved multifold.

FIG. 2 represents a design variation in which force to the pin end 7 of FIGS. l-a and l-b is now supplied to the pin end 7-a which being identical to part of pin 4 in said FIGS. l-a and l-b in all other respects, in FIG. 2 it becomes pin 4-a with addition of a seal groove 18 within pin end 7-a, said seal groove 18 being provided with appropriate elastomer seal 19 acts as a divider between the working fluid end of the housing identified by 20-a and the actuating pilot end of the housing identified as 20b. The housing 20 thus becomes divided into a 20-a section which in FIGS. La and l-b comprises a valve housing 1, and a 20-b section which in FIG. 2 is provided with a threaded pilot actuation port 21 connected to a pilot supply system, which in the illustrated case includes a valve 22 leading from a pilot supply and valve 23 leading to a pilot exhaust. With valve 22 open and valve 23 closed, port 21 is subjected to the full pressure of the pilot fluid supply. This pressure acting over the pin end 7-a, which in the illustrated case has slightly larger diameter than the forward section of the pin 4-a, identified by 8-a, and thus offering a mechanical advantage, exerts an end thrust over pin end 7-a in terms of an external force large enough to overcome the end thrust of the constantly supplied working fluid to the infeed bore 24 housing pin end 8-a with sea] 1 La, and to crack seal while shifting pin to assume a new position permitting fluid flow from the infeed port via annulus 17-a toward receiver port 16-a.

With the valve 22 closed and the valve 23 open,-port 21 experiences a pressure drop and a reduction of external force to the pin end 7-a, to subsequently result in the shift of the pin to the original position, as a result of the working fluid end thrust over the pin end 8-a with seal ll-a, which ultimately becomes pressed against the seat 24-a.

Seat24-a may be a countersunk shoulder of bore 3-a comprising a cylindrical part of axially extending housing bore provided therein and accommodating slidably pin 4-a in a similar manner as detailed while describing FIGS. La and l-b. Bore 3-a at the other end terminates with shoulder 6-a leading to enlarged bore cavity 25 wherein port 26 perpendicularly entering cavity 25 is located to act as fluid exhaust. A receiver port l6-a perpendicularly entering bore 3-a is provided with threads as shown in the drawing to connect to a load such as a power cylinder. Pin 4-a inside axially extending housing bore 3-a with smaller diameter 8-a exposed to the infeed 'end and larger diameter pin end 7-a received by the cavity 25 is provided with an additional seal 13-a situated at the shoulder 9-0 which in the illustrated case is away from the seat against the shoulder 6- a identifying condition with receiver port 16-a to exhaust while communicating via annulus 15-a.

In another case, not illustrated, the function of the.

pilot supply and exhaust via valves 22 and 23 may be performed by a solenoid valve which can be screwed into port 21 to perform an identical function of pilot operation by automatic means.

FIG. 3 shows a valve identical to the valve shown in FIG. 2 except that the exhaust port 26 and pilot port 21 of FIG. 2 are omitted here to make this valve a simple two-way pin operated valve, normally closed regardless of the direction of flow, also without any of the springs to keep this valve closed but only by the working fluid action over the exposed pin surfaces, unless external force is applied to the protruding pin end for valve actuation.

As seen from FIG. 3, valve housing 30 of elongated configuration having an axially extending cylindrical bore 31 is provided at fluid infeed end with enlarged bore 32, and a reduced size bore portion 33 in communication with receiver bore 34 and terminating with enlarged bore 35 at the housing end 36. Shoulder 32-a serves as valve seat. Pin 37 of diameters of which the smaller diameter 38 at the fluid entrance end 32-a is provided with a seal '39, is slidably received inside reduced bore 33, and terminates at the other valve actuator end with larger size 40, a portion of which is always retained within the enlarged bore portion 35, containing an elastomer seal 41, permanently secured in its respective groove 42, and the other portion of which protrudes outside the housing end 36 for valve actuation by the pin end 43. The seal 39 thus constitutes the pin stop during its axial shift from one position to another limited by the pin shoulder44 which separates the smaller and the larger diameters of said pin 37. Annulus 45 provides fluid communication means between entrance bore 32 and bore 34.

' As described in FIGS. 1 and 2, the operation of this valve depends primarily upon the working fluid end thrust within the valve proper by virtue of acting constantly over the seal 39 to press tightly against the valve seat 32-a at the valve entrance in order to keep it constantly closed, and requires opposing forces to be applied to the protruding pin end 43 of larger magnitude than said end thrust in order to crack seal 39 for fluid flow and subsequent communication with the receiver port 34 via annulus 45 created by clearances between the pin 37 outside diameter and bore 33 inside diameter provided therein. Upon removal of this external force from the pin end 43, pin 37 will shift back to the original position automatically because of fluid, end thrust exerted over the pin end provided with seal 39 and also additional end thrust exerted by the working fluid in the two-way valve design depicted in FIG. 3 over the pin shoulder 44. In the illustrated case the diameter of the pin shoulder 44 being inherently larger than the diameter of the pin end 38 provided with seal 39, it would make no difference whether the working fluid enteredvia bore 32 defined above as fluid entrance bore, or if it entered via port 34, defined above as receiver bore. In either case the end thrust of the larger diameter area would position the valve in the NORMALLY CLOSED position which usually requires the shift of the pin to the opposite direction for initiation of flow, such a shift necessitating an external force for valve actuation, be it manual direct, indirectthrough a linkage such as foot pedal, or direct cam or a tripper action as described in the previous paragraphs. In another case not shown in FIG. 3 but described in FIG. 2, this external force may be provided by incorporating simply either pilot port or a solenoid valve through a slight modification of housing end 36 which is considered obvious for those skilled in this art, without additional description of case in question.

FIG. 4 illustrating a four-way pin operated directional valve, which is actuated by external means by way of protruding pin, in operation is similar to'the operation of two-way valve described above. Turning to the description of FIG. 4 in more detail, it is seen to include an elongated housing 50 having an axially extending cylindrical bore 51 therein. The ends of bore 51 are enlarged in diameters; bore end 52 comprising a cylinder ONE exhaust end is in communication with a perpendicularly situated bore 53 leading to cylinder ONE which is threaded as shown in the-drawing, and bore end 54 comprising a cylinder TWO exhaust end is in communication with another perpendicularly situated bore 55 leading to cylinder TWO which is also threaded. The cylindrical bore 51 at each end terminates with shouldered openings due to diametral changes described, said openings serving as sealing surfaces for valve porting in which shoulder 52-a in the illustrated case is secured by an elastomer seal 59, and shoulder 54-a is unabstructed to permit fluid'flow into the cylinder TWO bore 55 as shown.

Bore 56 having threadedfluid entrance port for connecting to the working fluid supply line is in direct communication with the cylindrical bore 51 for serving alternatively either cylinder one or cylinder two depending on the location of the operator. In the illustrated case the cylinder one is to exhaust while the cylinder two is energized, because of the position of the operating pin 57. The pin 57 having smaller diameter 58 slidably received inside bore 51 and secured permanently by a seal 59 within its appropriate groove 60 to seal off cylinder ONE identifies a larger diameter shoulder 61 with its seal 62 away from the sealing surface 54-a which in turn enables communication of the working fluid between the entrance bore 56 and the cylinder TWO bore 55 via annulus 63 as a result of the end thrust exerted over the pin shoulder 61 inherently larger than the diameter of the pin end 58 secured by seal 59. To change the position of the pin providing cylinder TWO NORMALLY OPEN requires an application of an external force to the protruding pin end 64. Such force being slightly larger in magnitude than the internal fluid thrust over pin shoulder 61 will shift the position of the pin to the extent that the shoulder 54-a becomes a seat for the elastomer seal 62 altemating fluid supply from cylinder TWO to cylinder ONE while cylinder TWO exhausts via said bore end 54 for as long as the force over the pin end 64 is maintained. Upon the removal of force from the pin end 64, the pin 57 shifts automatically back, due to the described internal fluid thrust force over the pin shoulder 61, to the original NORMALLY OPEN CYLINDER TWO Position, while the cylinder ONE exhausts via bore end 52.

FIG. 5 represents a design variation .of FIG. 4 in that the operation of this four-way valve is not manual but pilot actuated. The addition of pilot operator to the four-way valve of FIG. 5 identifies an elongated housing 70 with an axially extending cylindrical bore 71 having an operating end 72 and a valving end 73, with seal 74 acting as a distinct divider between these ends. At the operating end, the port 75 is connected to a pilot fluid supply system which in the illustrated case vincludes a valve 76 leading from a pilot supply and a valve 77 leading to a pilot exhaust. With the valve 76 open and the valve 77 closed, the port 75 is subject to the full pressure of the pilot fluid supply. With the valve 76 closed and the valve 77 open, the port experiences a drop in fluid supply pressure down to substantially atmospheric pressure. At the valving end the port 78 may be connected to a working fluid supply source (not shown). It also communicates with axially extending cylindrical bore 71 to alternatively feed cylinder ONE port 79 or cylinder TWO port 80, both ports in the illustrated case are perpendicular to the bore 71 and are provided with threads as shown in the drawing. Bore 81 also situated perpendicularly to the bore 71 serves as cylinder TWO exhaust means, while the enlarged end 82 of the longitudinal bore 71 serves as exhaust means for cylinder ONE port 79.

A pin 83 of differential diameter of which smaller diameter end 84 is slidably received inside bore 71 and secured permanently by a seal 85 within its appropriate groove 86, in the illustrated case seals off fluid entrance to the cylinder port 79 as a result of seal 85 firmly pressed against the shoulder 82-a, and identifies cylinder ONE open to exhaust via port 82. The opposite pin end of larger diameter 87 having shoulder 88 provided with seal 89 in the illustrated case identifies cylinder TWO normally open to the working fluid flow form the fluid supply port 78 via annulus 90 and another'enlargement 91 of the bore 71 and terminating with sealing surface 91-a being unabstracted as shown in the drawing. Pin end 87 is also provided with an appropriate seal groove 92 for securing permanently said seal 74 which divides the operating end 72 from valving end 73. To change the position of the pin providing this normally open cylinder two condition requires an application of an external force to the pin end 93, which in the illustrated case is done by pilot pressure supply to the port 75 when valve 76 is open and valve 77 is closed. Upon closing valve 77, the pilot pressure will shift pin 83 to crack seal 85 for feeding and energizing the cylinder ONE while cylinder TWO will exhaust via exhaust port 81 because the seal 89 will firmly press against the sealing surface 91-a shutting off additional supply of the working fluid to the cylinder TWO, and direct it to cylinder ONE instead. When valve 77 is opened, and valve 76 closed, the pin will automatically return to the original cylinder TWO normally open position due to the working pressure thrust force exerted over the pin shoulder 88 of larger diameter and therefore larger force, to facilitate such automatic pin return to said original position without the use of springs, while the cylinder ONE returns to exhaust position as shown in the drawing.

The invention is not restricted to the slavish imitation of each and every one of the details described above which have been set forth merely by way of example with the intent of most clearly setting forth the teaching of the invention. Obviously, devices may be provided which change, eliminate, or add certain specific structural or procedural details without departing from the invention.

What is claimed is:

1. A valve for transmitting pressurized working fluid from a fluid supply to receiver means, such as an actuating power cylinder or a process batch, and for exhausting the transmitted fluid caused by a change of position of the internal valve components which are normally maintained fixed by the forces the working fluid exerts over their surfaces, such position change I060ll 0472 being the result of the application of an external force, be it manual, by a tripper or a cam of a machine, or by pilot pressure application, and an automatic return of such components to their original positions upon removal of such external forces due to the end thrust of the working fluid designed to maintain internal valve components situated exactly in their original positions without the use of springs but by the action of the working fluid pressure alone unless their positions are disturbed by said external forces, said vforces not amounting to too much because the internal forces are small due to the valve design providing effortless valve actuation, comprising a valve housing having an infeed end and a receiver port, a cylindrical axially extending bore, one end of which is enlarged and shouldered, a differential diameter-pin slidably received in the housing, and dividing the interior thereof into an infeed chamber for communication with a source of pressurized working fluid, an annular fluid passage means to the receiver port, a receiver exhaust means opposite to the said infeed chamber, a sealing means, said infeed chamber normally sealed from said annular fluid passage means by an elastomer seal permanently secured in an appropriate groove at the end of the smaller diameter of said differential diameter pin and constantly experiencing working fluid pressure in terms of end thrust forcing said sealtightly against said bore end shoulder, said pin having larger diameter shoulder pin portion substantially protruding valve housing end opposite to said infeed end, said pin shoulder having a sealing means for stopping fluid exhaust when the pin is actuated by external means to change its original position and to allow flow from said infeed chamber to said receiver port, while exhaust port means are kept sealed off externally, said exhaust port means opening into the atmosphere for fluid exhaust from said receiver port upon removal of said external forces due to said working fluid end thrust over the pin end at the infeed port to shift said pin to assume the original position wherein said infeed chamber is normally sealed off from said annular fluid passage means, constituting the normally closed valve position with receiver port to exhaust.

2. A valve as in the foregoing claim including an axial exhaust passage means opposite to said infeed end via annulus at the larger diameter shouldered pin provided with appropriate sealing means for stopping fluid exhaust by the application of external force, resulting in change of direction of flow from normally closed valve condition to cylinder feed condition while cylinder exhaust is closed, and return to the original valve normally closed condition upon removal of said external force, while the cylinder is to exhaust, typifying an operation of a three-way normally closed directional valve with exhaust through the pin annulus.

3. A valve as in the foregoing claims including a perpendicularly situated exhaust port substantially in line with the shoulder of larger diameter, situated axially, of differential diameter pin, said larger pin diameter provided with an additional elastomer seal of O-ring or quad-ring configuration secured permanently inside an appropriate groove and situated so that it never crosses said perpendicular exhaust port while serving as separating member means between a valving section of the housing and a pilot actuation section added thereto, said pilot actuation section extending longitudinally the said valve housing of which the infeed end is directly opposite to the pilot entrance port comprising an extension of said cylindrical axially extending housing bore, said pilot entrance port threaded for connecting to the pilot supply line means, said external force provided by the pilot pressure thrust over the larger diameter pin end exposed thereto for shifting of said pin and subsequent change of direction of flow from normally closed valve condition to cylinder feed condition while the exhaust is closed for as long as the pilot pressure exerts said end thrust to the larger diameter pin end within said pilot port, and upon removal of said pilot end thrust through pilot exhaust from said pilot port, a return to the original valve normally closed condition while the cylinder is to exhaust via said perpendicularly situated fluid exhaust from the valving section of the housing, typifying an operation of a three-way normally closed pilot operated directional valve effortlessly.

4. A valve as in claim 3 excluding a perpendicularly situated exhaust port substantially in line with the shoulder of large diameter of the pin, said larger diameter pin portion provided with additional elastomer seal of O-ring or quand-ring configuration permanently secured inside appropriate groove and situated so as to separate the valving section of the housing from the pilot actuation section added thereto, said valving section having no exhaust port means, said pilot actuation section extending longitudinally the said valve housing of which the infeed end is directly opposite to the pilot entrance port, and comprising an extension of said cylindrical axially extending housing bore,'said pilot supply pressure constituting an external force'necessary for shifting said pin inside saidvalving section to open fluid communication means between the infeed port and the receiver port means for a period as long as the external force prevails, and upon removal of said external force, a return to the original valve normally closed condition automatically as a result of the working fluid pressure end thrust over said pin surfaces, typifying an operation of a two-way normally closed pilot operated process control valve effortlessly, and without the use of any springs for the operation of said valve.

5. A valve as in claim 4 including an extension of the larger diameter pin to protrude outside the valve body opposite the valve infeed end for a manual valve operation in lieu of pilot operation, typifying an operation of a two-way normally closed process control valve actuated by external means be it manual or otherwise applied force to the protruding pin end.

6. A fluid valve for selectively porting fluid from a source to a load comprising housing means, fluid infeed means, first port means in said housing for receiving fluid under pressure and for its exhaust, second port means for receiving fluid under pressure and for its exhaust, cylindrical axially extending housing bore, valving means in said housing comprising a slidably received differential diameter pin inside said cylindrical housing bore to float by shifting from a first position blocking communication between said first port means which is open to exhaust to the second position for fluid communication between fluid infeed and first port means while second port means are disconnected from the fluid supply means and are open to exhaust, and an automatic return to the original position, said pin shiftl060l l 0473 ing inside said cylindrical housing bore performed by external means forcing a change of its natural location as controlled by the working fluid to assume temporarily an opposite position which redirects the flow of the pressurized fluid to feed alternatively the first port means when externally energized, and vice versa, and means for maintaining said valve means in one of said positions without the influence of biasing force on said valve means.

7. A valve as in the foregoing claims including means for maintaining the valve means in normally closed position and means for changing of said position, said normally closed position attained by the working fluid action in terms of end thrust over the exposed valve means tothe pressurized fluid, and said position change attained by shifting the valving means by external means, such external means comprising a force applied 1 to the valving means either by pilot pressure or by physically applying a manual or a machine force larger than the force the working fluid exerts over the valving means internally.

8. A fluid valve as defined in the foregoing claims wherein the external force means are applied to the pin end larger'in diameter than the pin end exposed to the working fluid pressure end thrust with a resultant mechanical advantage incorporated in the operation of the valve during the position change from said normally closed position to other positions wherein said external force may be decreased to balance the valve means.

9. A pilot operated valve comprising valve housing means, first port means in said housing means adapted to be connected to a source of the working fluid under pressure, second port means insaid housing adapted to be connected to a load, exhaust port means, a valve member slidably received inside cylindrical axially extending differential diameter housing bore to shift from a first position blocking communication between the first and second port means to a second position communicating said first and second port means, pilot piston means in said housing means communicating with third port means and connected to shift said valving means from one of said positions to the other of said positions and urging said valve member to said first position, and fluid operable for shifting said valve member to said second position.

10. A pilot operated valve as defined in the foregoing claims wherein said valve member is maintained in said first position solely by the pressure of the working fluid, and the second position solely by the relative pressure in said pilot port means and said fluid operable means.

11. A pilot valve operated as in the foregoing claims including valving means for porting fluid to said fluid operable means, said valving means being in said housing means, said valving means including an axially slidable differential diameter pin having a valving surface at one end and an actuating surface at the other valve housing end.

l060ll 0474 

1. A valve for transmitting pressurized working fluid from a fluid supply to receiver means, such as an actuating power cylinder or a process batch, and for exhausting the transmitted fluid caused by a change of position of the internal valve components which are normally maintained fixed by the forces the working fluid exerts over their surfaces, such position change being the result of the application of an external force, be it manual, by a tripper or a cam of a machine, or by pilot pressure application, and an automatic return of such components to their original positions upon removal of such external forces due to the end thrust of the working fluid designed to maintain internal valve components situated exactly in their original positions without the use of springs but by the action of the working fluid pressure alone unless their positions are disturbed by said external forces, said forces not amounting to too much because the internal forces are small due to the valve design providing effortless valve actuation, comprising a valve housing having an infeed end and a receiver port, a cylindrical axially extending bore, one end of which is enlarged and shouldered, a differential diameter pin slidably received in the housing, and dividing the interior thereof into an infeed chamber for communication with a source of pressurized working fluid, an annular fluid passage means to the receiver port, a receiver exhaust means opposite to the said infeed chamber, a sealing means, said infeed chamber normally sealed from said annular fluid passage means by an elastomer seal permanently secured in an appropriate groove at the end of the smaller diameter of said differential diameter pin and constantly experiencing working fluid pressure in terms of end thrust forcing said seal tightly against said bore end shoulder, said pin having larger diameter shoulder pin portion substantially protruding valve housing end opposite to said infeed end, said pin shoulder having a sealing means for stopping fluid exhaust when the pin is actuated by external means to change its original position and to allow flow from saId infeed chamber to said receiver port, while exhaust port means are kept sealed off externally, said exhaust port means opening into the atmosphere for fluid exhaust from said receiver port upon removal of said external forces due to said working fluid end thrust over the pin end at the infeed port to shift said pin to assume the original position wherein said infeed chamber is normally sealed off from said annular fluid passage means, constituting the normally closed valve position with receiver port to exhaust.
 2. A valve as in the foregoing claim including an axial exhaust passage means opposite to said infeed end via annulus at the larger diameter shouldered pin provided with appropriate sealing means for stopping fluid exhaust by the application of external force, resulting in change of direction of flow from normally closed valve condition to cylinder feed condition while cylinder exhaust is closed, and return to the original valve normally closed condition upon removal of said external force, while the cylinder is to exhaust, typifying an operation of a three-way normally closed directional valve with exhaust through the pin annulus.
 3. A valve as in the foregoing claims including a perpendicularly situated exhaust port substantially in line with the shoulder of larger diameter, situated axially, of differential diameter pin, said larger pin diameter provided with an additional elastomer seal of O-ring or quad-ring configuration secured permanently inside an appropriate groove and situated so that it never crosses said perpendicular exhaust port while serving as separating member means between a valving section of the housing and a pilot actuation section added thereto, said pilot actuation section extending longitudinally the said valve housing of which the infeed end is directly opposite to the pilot entrance port comprising an extension of said cylindrical axially extending housing bore, said pilot entrance port threaded for connecting to the pilot supply line means, said external force provided by the pilot pressure thrust over the larger diameter pin end exposed thereto for shifting of said pin and subsequent change of direction of flow from normally closed valve condition to cylinder feed condition while the exhaust is closed for as long as the pilot pressure exerts said end thrust to the larger diameter pin end within said pilot port, and upon removal of said pilot end thrust through pilot exhaust from said pilot port, a return to the original valve normally closed condition while the cylinder is to exhaust via said perpendicularly situated fluid exhaust from the valving section of the housing, typifying an operation of a three-way normally closed pilot operated directional valve effortlessly.
 4. A valve as in claim 3 excluding a perpendicularly situated exhaust port substantially in line with the shoulder of large diameter of the pin, said larger diameter pin portion provided with additional elastomer seal of O-ring or quand-ring configuration permanently secured inside appropriate groove and situated so as to separate the valving section of the housing from the pilot actuation section added thereto, said valving section having no exhaust port means, said pilot actuation section extending longitudinally the said valve housing of which the infeed end is directly opposite to the pilot entrance port, and comprising an extension of said cylindrical axially extending housing bore, said pilot supply pressure constituting an external force necessary for shifting said pin inside said valving section to open fluid communication means between the infeed port and the receiver port means for a period as long as the external force prevails, and upon removal of said external force, a return to the original valve normally closed condition automatically as a result of the working fluid pressure end thrust over said pin surfaces, typifying an operation of a two-way normally closed pilot operated process control valve effortlessly, and without the use of any springs for The operation of said valve.
 5. A valve as in claim 4 including an extension of the larger diameter pin to protrude outside the valve body opposite the valve infeed end for a manual valve operation in lieu of pilot operation, typifying an operation of a two-way normally closed process control valve actuated by external means be it manual or otherwise applied force to the protruding pin end.
 6. A fluid valve for selectively porting fluid from a source to a load comprising housing means, fluid infeed means, first port means in said housing for receiving fluid under pressure and for its exhaust, second port means for receiving fluid under pressure and for its exhaust, cylindrical axially extending housing bore, valving means in said housing comprising a slidably received differential diameter pin inside said cylindrical housing bore to float by shifting from a first position blocking communication between said first port means which is open to exhaust to the second position for fluid communication between fluid infeed and first port means while second port means are disconnected from the fluid supply means and are open to exhaust, and an automatic return to the original position, said pin shifting inside said cylindrical housing bore performed by external means forcing a change of its natural location as controlled by the working fluid to assume temporarily an opposite position which redirects the flow of the pressurized fluid to feed alternatively the first port means when externally energized, and vice versa, and means for maintaining said valve means in one of said positions without the influence of biasing force on said valve means.
 7. A valve as in the foregoing claims including means for maintaining the valve means in normally closed position and means for changing of said position, said normally closed position attained by the working fluid action in terms of end thrust over the exposed valve means to the pressurized fluid, and said position change attained by shifting the valving means by external means, such external means comprising a force applied to the valving means either by pilot pressure or by physically applying a manual or a machine force larger than the force the working fluid exerts over the valving means internally.
 8. A fluid valve as defined in the foregoing claims wherein the external force means are applied to the pin end larger in diameter than the pin end exposed to the working fluid pressure end thrust with a resultant mechanical advantage incorporated in the operation of the valve during the position change from said normally closed position to other positions wherein said external force may be decreased to balance the valve means.
 9. A pilot operated valve comprising valve housing means, first port means in said housing means adapted to be connected to a source of the working fluid under pressure, second port means in said housing adapted to be connected to a load, exhaust port means, a valve member slidably received inside cylindrical axially extending differential diameter housing bore to shift from a first position blocking communication between the first and second port means to a second position communicating said first and second port means, pilot piston means in said housing means communicating with third port means and connected to shift said valving means from one of said positions to the other of said positions and urging said valve member to said first position, and fluid operable for shifting said valve member to said second position.
 10. A pilot operated valve as defined in the foregoing claims wherein said valve member is maintained in said first position solely by the pressure of the working fluid, and the second position solely by the relative pressure in said pilot port means and said fluid operable means.
 11. A pilot valve operated as in the foregoing claims including valving means for porting fluid to said fluid operable means, said valving means being in said housing means, said valving means including an axially slidable differential diameter pin having a valving surface at one end and an actuating surface at the other valve housing end. 